Help with DLTCEP (saving edits)

I have a question regarding the DLTC editor. When I make changes in a character's dialog (like TEXT#1, for example), the changes are saved automatically when I close the editor, but when I make other changes (like changing the dialog condition) I can't figure out how to save the change. I have the READ ONLY option unchecked, and I click the SAVE command, but when I close the editor the condition reverts back to what it was. If I use the SAVE AS command, I can save the data into the character's override file, but that doesn't seem to do anything. Why does the editor let me make changes (and save them) but fail to retain them?